Smoke composition

ABSTRACT

The invention relates to a smoke composition comprising between 0.05 and 5% of one or more active ingredients, for an effective dose of active ingredient(s) of between 0.5 mg/m 3  and 40 mg/m 3 , and a smoke base. According to the invention, the aforementioned smoke base comprises at least one oxidising agent, one reducing agent and one mineral filler. The mineral filler represents at least 25% of the weight of the base while the reducing agent represents at most 16% of the weight thereof, and the weight ratio of oxidising agent to reducing agent is at least 3/1.

The invention relates to a smoke composition comprising a smoke base andone or more active substances, generally biocidal and/orphytopharmaceutical active substances.

In the present description, the expression “biocidal and/orphytopharmaceutical active substance” is intended to mean a chemicallydefined and non-formulated substance, used in order to combat thepresence of organisms or of microorganisms considered to be pests.

In the remainder of this patent, the expression “active ingredient of asmoke” will be used to refer to the active substance or all the activesubstances used in the smoke. Similarly, the term “concentration ofactive ingredient” will refer to the sum of each of the concentrationsof the active substances, present in the smoke, out of formulation.

Fumigation is a technique which, through the combination of asubstantial and abrupt increase in temperature, and a subsequentgeneration of gas, makes it possible to very effectively andhomogeneously disperse, in the air, one or more active substances in theform of a very fine, generally at least microscopic, solid and/or liquidaerosol, or else of a gas.

Experience shows that aerosol and/or gas can get into the slightestnooks and crannies, which, combined with its great fineness, allowsparticularly effective treatment.

A smoke composition or preparation consists of an autoreactive base,that heats rapidly and greatly, its temperature possibly reachingseveral hundred degrees between a few seconds and a few minutes, whileat the same time releasing a considerable amount of gas, and of one ormore active substances, in the form of a powder, of a liquid or of apaste, optionally impregnated on a support, which, under the combinedaction of the abrupt increase in temperature and the emission of gas,will be finely dispersed, in the form of a liquid and/or solid aerosol.

The fields of application of smokes are, in general, those ofdisinfection and treatment with insecticide in agrofoods industries,livestock rearing, seed or harvest storage and transport, greenhouses orsheds, hospitals, community premises, domestic premises, etc. Of course,the scope of the present invention is not limited to these applications,even though its description hereinafter is given with reference to abiocidal and/or phytopharmaceutical use.

The diffusion of an active ingredient with pharmaceutical action, byinhalation, in human or veterinary medicine can, for example beenvisioned.

Before continuing, some notions linked to the use of the smoke should bedefined, concentrating more particularly on disinfectant or insecticidalsmokes.

A smoke treatment or fumigation consists in initiating the combustion ofa smoke preparation containing an active ingredient, the amount of whichis in relation to the volume of the room to be treated, said room beingmade draughtproof beforehand.

A sufficient contact time, generally of several hours, is maintainedbetween the smoke emissions and the closed room.

The term “fumigation time” will be used to denote the time during whichthe smoke effectively smokes and the term “contact time” will be used todenote the total period during which the room to be treated iseffectively in contact with the emissions.

The term “fumigation” defines the treatment in its entirety.

In general, the effectiveness of a disinfectant/insecticidal smoke isdetermined, at the end of this predetermined contact time, either by theproportion of target organisms that have been destroyed on a surface,compared with a nontreated control, or by the quantitative decrease inthe amount of damage engendered by these organisms at the smoke user'spremises.

The term “effective smoke” or the expression “good effectiveness of asmoke” will be used if said smoke attains a proportion of destroyedtarget organisms that is compatible with quantitative requirementsprefixed by standards, laws, administrative procedures, or a company'sor an authority's internal regulations, or by simple experience in thefield, or if the level of damage caused by the target organisms afterfumigation is considered to be acceptable by the user.

The effective dose of an active ingredient is the amount of activeingredient theoretically dispersed in the atmosphere of the premises tobe treated, that is necessary for an effective treatment. This dose isgenerally expressed in mg/m³. It corresponds in fact to the amount ofactive ingredient initially present in the smoke, divided by the volumeto be treated. At the current time, the effective doses of activeingredient for a disinfectant smoke are of the order of 30 to 160 mg/m³and, for an insecticidal smoke, of the order of 6 to 50 mg/m³.

The effective dose of a smoke composition is expressed by the number ofgrams of smoke composition per cubic meter (g/m³), that provideseffective treatment within the meaning defined above. By way ofillustration, the values of the effective doses for insecticidal smokecompositions are of the order of 0.2 to 2 g/m³ and, for disinfectantsmoke compositions, of the order of 0.3 to 1.5 g/m³.

However, of course, the effective dose of a smoke depends on theconcentration and on the effectiveness of the active ingredient, on thecontact time and on the use.

The term “ground residues” is intended to mean all the products that areon the ground after fumigation, i.e. smoke degradation products, butalso active ingredient and constituents of the smoke.

The term “emissions” is intended to mean all the compounds emitted intothe air by the smoke base, i.e. all the aerosols and gases.

Unlike the products referred to as “fumigating products” that give offhighly toxic gases and are reserved for specialist teams, or even teamssubject to authorization, smokes can be handled by individuals who arenot technicians, and in particular the public at large, even though, ingeneral, the treatment per se is carried out with no human presence.

Consequently, it would be necessary to have smoke compositions which,besides good effectiveness, have the following properties:

-   -   easy to use, in particular in terms of lighting, which must be        done readily, but with no flame nor an explosion,    -   little odor, persistent or otherwise,    -   few ground residues,    -   residues and emissions that are relatively nontoxic with respect        to the environment and to humans, and that are clearly        identifiable,    -   no projection of hot products out of the container,    -   entirely safe production, transport, storage and handling, in        terms of both the dangers of catching light or even exploding,        and the toxicity of the smoke product in itself.

Currently, a compromise is generally reached with smoke bases comprisingan oxidoreductive system which engenders the action of abrupt heatingand the release of gas, the oxidizing agent generally being nitrate-,chlorate- or perchlorate-based, and the reducing agent being nitrogenouscompound- or carbon compound-based, and excipients that are involved inthe quality of the ignition, or in the combustion so that it is even andwithout flames, or that facilitate the handling.

However, these compositions have various drawbacks. They still have toostrong an odor during and after fumigation, and they generateconsiderable amounts of ground residues, that are mainly organic. Theresidues are sometimes toxic and dirty, and have a poorly definedgeneral composition. In addition, they often have the effect ofdecreasing the effectiveness of the active ingredient. The amount of dryground residues of these smoke compositions is generally between 5 and15% of the initial mass thereof.

Such compositions are, for example, described in the followingdocuments.

Document JP-03-086804 describes an insecticidal or fungicidal smokecomposition, the smoke base of which comprises potassium chlorate, areducing agent such as glucose or starch, a thiourea derivative (1-30%)and, optionally, a mineral filler chosen from clay and talc, melamine asa combustion regulating agent and carboxymethylcellulose.

Document FR-A-2 096 873 discloses a smoke composition comprisingammonium nitrate in a proportion of the order of 42% by weight of thetotal weight of the composition, dicyandiamide in a proportion of theorder of 28%, as a reducing agent, 0.5% to 20% of a mineral filler whosefunction is to act as a heat screen, and from 5% to 10% of a fungicidalor bactericidal active ingredient.

According to document FR-A-2 637 459, an insecticidal, bactericidal orfungicidal smoke composition is known, the smoke base of which comprisesammonium nitrate (at least 42% by weight of the final weight of thebase), dicyandiamide (at least 28% by weight) as a reducing agent,silica (approximately 10%) and a chlorinated compound in liquid or solidform.

The large amount of residues generated by these compositions of theprior art constitutes a major drawback thereof.

These residues are essentially the result of the degradation, during thefumigation, of the reducing agent and of the active ingredient, which,in these compositions, often represent, by weight, around a third, oreven more, of the final composition. This degradation, besides producingresidues which can lead to a certain toxicity for humans or theenvironment, makes it necessary to increase the amount of activeingredient initially present, in order to reach the required level ofeffectiveness.

To solve this problem, the applicant has sought a smoke base which,while having the abovementioned properties, namely effectiveness, easyhandling and limited risks of projection, of ignition and of explosion,would make it possible to decrease the proportion of the reducing agentand of the active ingredient while increasing the effectiveness of thelatter.

The applicant has thus discovered a highly effective smoke base, theproperties of which will be illustrated later in the description, inwhich the proportion of the reducing agent is greatly reduced comparedwith that of the above compositions, and which makes it possible toobtain an effective composition with an amount of active ingredient thatis much lower than those of the known compositions.

One of the advantages of the invention is therefore to decrease theinitial amount of active ingredient used for treating one m³ of air.This means that, for the same effective dose of smoke, the proportion ofactive ingredient in the smoke is quite sizably decreased.

Of course, it is not a question of increasing the effective dose ofsmoke, for example from 1 g/m³ to 2 g/m³, in order to decrease, in thesame proportion, the concentration of active ingredient in said smoke,for example from 10% to 5%.

Unexpectedly, a correct fumigation reaction with a small proportion ofreducing agent is obtained by adding a large proportion of mineralfiller, which, normally, is chemically barely reactive.

Just as unexpectedly, the applicant has also discovered that the use ofthis base makes it possible to significantly decrease the proportion ofactive ingredient in the air and therefore in the composition, withoutthe effectiveness of the composition obtained being affected.

Since the applicant uses, for practical reasons, effective doses ofbactericidal, fungicidal and insecticidal smoke of 0.1 g/m³ to 3 g/m³,the concentrations of active ingredient in the smoke which is thesubject of the present invention are of the order of 0.05% to 5%, inorder to obtain a theoretical dose of active ingredient in the air ofthe order of 0.5 mg/m³ to 40 mg/m³.

As mentioned above, the values of the effective doses for aninsecticidal active ingredient in the current smokes are of the order of6 to 50 mg/m³ and, for a disinfectant smoke, of the order of 30 to 160mg/m³.

For smokes used at different doses, it would of course be necessary tocorrect, in proportion, the concentration of active ingredient in thesmoke.

Similarly, the above doses only apply for fungicidal, bactericidal andinsecticidal applications.

For other applications, it is quite obvious that said doses may bedifferent.

Thus, a first subject of the invention is a smoke composition comprising0.05 to 5% of one or more active ingredients, for an effective dose ofactive ingredient(s) of 0.5 mg/m³ to 40 mg/m³, and a smoke base; saidsmoke base comprises at least one oxidizing agent, one reducing agentand one mineral filler, the mineral filler representing at least 25%,advantageously between 25 and 65%, by weight of said base, the reducingagent at most 16%, advantageously between 2 and 13%, by weight of saidbase, and the ratio by weight of said oxidizing agent to said reducingagent being at least 3/1.

Compared with the known compositions, the proportions of reducing agentand of active ingredient are greatly reduced, and the ratio of oxidizingagent to reducing agent is high, which results in compositions for whichthe fumigation engenders much fewer residues.

According to the invention, the mineral filler is at least partiallyfunctional and comprises at least one aerating agent, one catalystand/or one regulating agent.

In the remainder of the text, the term “compound” will be used for asingle product, and the term “agent” will be used for a compound or amixture of compounds satisfying at least one specific function in thefumigation.

Before disclosing in greater detail the characteristics and advantagesof the invention, certain terms used in the description and the claimsare defined.

An aerating agent is a compound or mixture of compounds that facilitatethe evacuation of the gases during the fumigation.

It therefore prevents, during the eruption of the gases which occursduring the combustion, the formation of an overpressure which can resultin hot materials being ejected out of the container.

As a result of this, it also has the effect of facilitating the exit ofthe active ingredient.

According to the invention, an aerating agent is in the form of apowder, with a small particle size, and with a low apparent densitycompared with the real density, and the shape of the particles of whichpromotes the passage of gases.

By way of counterexample, clay, due to the lamellar structure of itsparticles, is not a good aerating agent.

A combustion-regulating agent is a compound or mixture of compoundswhose aim is to make sure that the fumigation is as even as possible,and to prevent said fumigation becoming too vigorous or too weak. Thisregulation can take place by vapors being given off which evacuate someof the energy of the oxido-reduction.

In parallel, the aim of these vapors may also be to facilitate the exitof the active ingredient, by entrainment, and to protect this sameactive ingredient against reactive compounds capable of degrading it,such as oxidizing gases (nitrogen oxides and N₂O).

An agent that catalyzes the combustion is a compound or mixture ofcompounds that facilitates the triggering and the maintenance of thereaction. The catalyst allows the fumigation to be initiated with anignition system that is reasonably powerful, in particular in terms ofrisks during handling, and the reaction to be self-maintaining.

A smoke composition according to the invention emits or releases anaerosol or a gas, generally intended to destroy or to controlmicroorganisms, insects or other unwanted invaders. It consists of a setof compounds comprising at least the smoke base and the activeingredient, the latter being advantageously chosen from bactericidal,fungicidal, virucidal, yeast-destroying, insecticidal, and acaricidalagents, and also having to possess good resistance to heat and tooxidation, and to readily vaporize.

The active ingredient is introduced into the smoke composition, insolid, liquid or pasty form.

By way of illustration, the C.E.B. insecticidal test protocol No. 135aand the airborne disinfection standard NFT 72-281 may be considered.

With a base of the invention, effectiveness according to the C.E.B.insecticidal test protocol No. 135a, for an active ingredient, at thedose of 1.5 mg/m³ is unexpectedly observed, whereas, with a conventionalbase and this same active ingredient, the effective dose is 9 mg/m³.

Using another base of the invention, it is also unexpectedly observedthat a disinfectant smoke composition can be effective within themeaning of standard NFT-72-281 in terms of fungal and bacterialdestruction, with an active ingredient at a dose of 2 mg/m³ versus 100mg/m³ previously with the same active ingredient.

A smoke base of the invention therefore makes it possible, in comparisonwith the known smoke bases and at comparable effectiveness, to decreaseboth the proportion of the reducing agent and that of the activeingredient, which are the two main sources of residues after fumigation.

Other preferential characteristics of the invention, considered alone orin combination, and making it possible to obtain the abovementionedadvantages, are disclosed hereinafter.

Thus, said base may comprise, relative to the final weight of the base,from 2% to 14%, preferably 8 to 12% by weight of said aerating agent andfrom 0.5 to 10%, preferably 3 to 5% by weight of said catalyst, and from12 to 60% by weight, preferably from 23 to 42% of said regulating agent.

Certain compounds can perform several functions; they may thus be bothcatalysts and regulating agents or aerating agents and regulatingagents. In this case, the proportion in the base of such a compound canreach the proportion of catalyst or aerating agent, plus, if necessary,the proportion of regulating agent.

Clay and magnesium chloride hexahydrate, phosphates and polyphosphatesare preferential catalyst and regulating compounds.

Inorganic hydroxides, carbonates and bicarbonates are aerating andregulating compounds.

Among these, aluminum hydroxide, magnesium hydroxide and iron hydroxide,calcium carbonate, magnesium carbonate, sodium carbonate and potassiumcarbonate, that may or may not crystallize with water, are preferentialaerating and regulating compounds.

The simple aerating compounds are advantageously chosen from silica,such as precipitated silica or vaporized silica, kieselguhr, talc,silicates, iron oxide, aluminum oxide, magnesium oxide and calciumoxide, aluminum sulfate, magnesium sulfate, calcium sulfate, potassiumsulfate, sodium sulfate and barium sulfate, and mixtures of thesecompounds.

The simple catalyst compounds are advantageously chosen from halogenatedinorganic salts, including ammonium-based salts, and/or inorganic ororganic copper salts and/or titanium oxide TiO₂ and mixtures thereof.

Among these, the preferential catalyst compounds are chosen from sodiumchloride, sodium iodide, potassium chloride, potassium iodide, calciumchloride, calcium iodide, magnesium chloride, magnesium iodide, ammoniumchloride, ammonium iodide, copper chloride, copper iodide, cupric oxideCuO, and titanium oxide TiO₂.

The simple regulating compounds are advantageously chosen from ammoniumcarbonates, ammonium bicarbonates and ammonium carbamates, and inorganicsalts that crystallize with water molecules, other than the abovecompounds defined for the aerating and regulating compounds.

The reducing agent comprises one or more organic compounds to which oneor more inorganic compounds may be added.

The organic compound is advantageously chosen from carbon derivatives,in particular highly carbonated compounds of simple formula, such ascharcoal, carbon black, graphite or paraffin, carbohydrates, such asstarch and cellulose and derivatives, polyols such as pentaerythritol,sorbitol, glycols such as glycerol, propylene glycol, and organic acidsand the salts of said acids, said acids or salts containing at most 9carbon atoms, preferably at most 7 carbon atoms.

The term “carbohydrate” is intended to mean mono- andpolyhydroxyaldehydes, mono- and polyhydroxy ketones, in particular mono-and polysaccharides, their derivatives such as mono- and polyhydroxyacids, and mono- and polyhydroxyamines.

By way of example, advantageous carbohydrates are the various sugars,starch and its derivatives, and cellulose and its derivatives.

Starch constitutes an advantageous reducing agent according to theinvention.

Another advantageous reducing agent according to the invention is chosenfrom salified or unsalified organic hydroxy acid, such as tartaric acid.

The reducing agent may also comprise at least one other organiccompound, in particular chosen from urea, dicyandiamide, melamine andcyanamide, and their salts, azodicarbonamide, guanidine and its salts,biguanide and its salts, methylcarbazate and ethylcarbazate.

The proportion of these nitrogenous compounds cannot then exceed 12% byweight relative to the base.

The reducing agent may also comprise at least one inorganic reducingcompound. The inorganic compounds are advantageously chosen from sulfurand sulfur oxides, which may or may not be anhydrous; preferably,anhydrous or nonanhydrous sodium thiosulfate Na₂S₂O₃. This isadvantageously present in a proportion ranging from 1 to 6% by weightrelative to the weight of the base.

The oxidizing agent of said base is advantageously chosen from nitrates,nitrites, chlorates and perchlorates, iodates and periodates, andperoxides, alone or as a mixture. Its preferential proportion in saidbase ranges from 30 to 70% by weight, and preferably from 40 to 60%.Thus, in a preferred variant, the oxidizing agent contains ammoniumnitrate, present in a proportion ranging from 40 to 60% by weightrelative to the weight of the base.

The oxidizing agent may comprise from 30 to 70% by weight of said base,preferably 40 to 60%, at least of two different nitrates. For example,it comprises from 4 to 16% by weight of said base, of potassium nitrate,sodium nitrate and/or calcium nitrate.

It may also comprise from 1 to 9% by weight of said base, of coppernitrate, aluminum nitrate or magnesium nitrate. It may also comprise atleast one peroxide chosen from inorganic peroxyhydrated salts.

A preferred composition according to the invention comprises a baseincorporating:

-   -   from 3 to 15% by weight of starch, and/or    -   from 6 to 12% by weight of silica, and/or    -   from 2 to 7% by weight of a chlorate or of a perchlorate or of        an iodate or of a periodate, and/or    -   from 2 to 7% by weight of a nitrite.

Better still, said base comprises from 35 to 45% by weight of ammoniumnitrate, from 5 to 12% by weight of sodium nitrate or potassium nitrate,from 6 to 12% by weight of starch, from 4 to 9% by weight of ahydroxycarboxylic acid or of its salt containing at most 6 carbon atoms,from 7 to 10% by weight of silica, and the rest in clay.

Such a base may also comprise one or more halogenated salts, in aproportion ranging from 1 to 7% by weight of the base.

Another subject of the invention is a smoke composition comprising atleast one smoke base as defined above and an active ingredient.

The disinfectant effectiveness of a smoke composition is measuredaccording to a technique described below, which is the subject of AFNORstandard, NFT 72-281.

This technique consists in providing, in a room where the fumigationwill take place, test microbe-carriers, i.e. plates made of awell-defined material, covered with dried solution, or inoculum,containing a known number of identical microorganisms of the samestrain.

Identical control microbe-carriers, not subjected to the emissions, arethemselves also placed in the room.

After a predetermined contact time with the smoke emissions, the numberof microorganisms that have survived in the test and controlmicrobe-carriers is determined by conventional microbiological methods.

The effectiveness is then given by the ratio of the number ofmicroorganisms of the control microbe-carrier to that of the testmicrobe-carrier.

If the bactericidal effectiveness of a composition is measured, aproduct is said to be bactericidal according to this standard if thenumber of viable bacteria has been divided by a ratio of 10⁵ withrespect to the number of viable bacteria present in the control sample.

If the fungicidal effectiveness of a composition is measured, a productis said to be fungicidal according to this standard if the number ofviable molds has been divided by a ratio 10⁴ with respect to the numberof viable molds in the control sample.

EXAMPLE 1 Disinfectant Smoke Composition According to the Invention

NH₄NO₃ 40%  KNO₃ 4% NA₂S₂O₃ 1% 4′-Hydroxysalicylanilide 0.5%   Starch 7%Urea _(2%) TiO₂ 1% Clay qs 100% (i.e. 44.5%)

At the dose of 1 g/m³, for a contact period of 15 hours, this smokecomposition has, according to the standard NFT 72281, an effectivenessof 1.8 log on Aspergillus niger.

EXAMPLE 2 Conventional Smoke Composition

NH₄NO₃ 48% Dicyandiamide 32% Precipitated silica 10%4′-Hydroxysalicylanilide 10% 100% 

EXAMPLE 3 Comparison Between the Smoke Composition According to theInvention Described in Example 1 and the Conventional Smoke CompositionDescribed in Example 2

The conventional smoke composition has a disinfectant effectivenessequivalent to that of the composition of example 1, but with a muchhigher dose of active ingredient per m³. In addition, the odor is muchstronger, and the amount of ground residues is clearly greater.

By way of example, the ground residue of the formulation of example 1 isbetween 0.5% and 2% of the initial mass of the composition, whereas thatof the formulation of example 2 is between 10 and 15%.

Whether the bactericidal effectiveness or the fungicidal effectivenessof the composition is measured, the composition of example 2 has aneffectiveness of 1 g/m³ of initial powder, for a contact time of 15hours.

EXAMPLE 4

Insecticidal Effectiveness of a Smoke Containing Bifenthrin FormulaPremix Al(OH)₃ 10.0%  Bifenthrin 1.5%

The bifenthrin is premolten, so as to be absorbed onto the aluminumhydroxide. This premix is then added to the following base of theinvention: NH₄NO₃ 50.0% Precipitated silica 10.0% Clay 19.5% Starch 9.0% 100.0% 

This smoke is tested at the dose of 0.1 g/m³, therefore at 1.5 mg/m³ ofbifenthrin, according to the C.E.B. protocol No. 135a.

The species tested are:

-   Blattella germanica-   Plodia interpunctella-   Tribolium confusum-   Rhizopertha dominica-   Musca domestica-   Ctenocephalides felis.

Result: After exposure for 4 hours, none of the insects have survived.

A conventional usage dose for a smoke is 9 mg/m³ of bifenthrin, i.e.clearly more than the dose of 1.5 mg/m³ used in the smokes of thepresent invention.

In addition, the ground dry residue can be estimated at approximately 1%of the initial mass of the smoke, and consists essentially, besides thebifenthrin, of ammonium nitrate, which is not very toxic at all.

For this smoke composition, if premises of 1000 m³, 4 meters high, aretaken into consideration, the ground dry residue will be of the order of4 mg/m², if the surface of the walls and ceilings are not taken intoaccount.

This will therefore be an extremely small amount.

1. A smoke composition comprising 0.05 to 5% of one or more active ingredients, for an effective dose of active ingredient(s) of 0.5 mg/m³ to 40 mg/m³, and a smoke base, characterized in that the smoke base comprises at least one oxidizing agent, one reducing agent and one mineral filler, the mineral filler representing at least 25% by weight of said base, the reducing agent at most 16% by weight of said base, and the ratio by weight of said oxidizing agent to said reducing agent being at least 3/1.
 2. The smoke composition as claimed in claim 1, characterized in that said base comprises from 2% to 13% by weight of reducing agent, and from 25% to 65% by weight of mineral filler.
 3. The smoke composition as claimed in claim 1, characterized in that the mineral filler comprises at least one aerating agent, one catalyst and one regulating agent.
 4. The smoke composition as claimed in claim 3, characterized in that said base comprises, relative to the final weight of the base, from 2 to 14%, preferably 8 to 12% by weight of said aerating agent, from 0.5 to 10%, preferably 3 to 5% by weight of said catalyst, and from 12 to 60% by weight, preferably from 23 to 42% of said regulating agent.
 5. The smoke composition as claimed in claim 3, characterized in that the compounds of the aerating agent are chosen from silica, kieselguhr, silicates, iron oxide, aluminum oxide, magnesium oxide and calcium oxide, talc, aluminum sulfate, magnesium sulfate, calcium sulfate, potassium sulfate, sodium sulfate and barium sulfate, and mixtures of these compounds.
 6. The smoke composition as claimed in claim 5, characterized in that the silica is precipitated or vaporized silica.
 7. The smoke composition as claimed in claim 3, characterized in that at least one catalyst compound of the catalyst is chosen from halogenated inorganic salts, including ammonium-based salts, inorganic or organic copper salts, and titanium oxide TiO₂.
 8. The smoke composition as claimed in claim 7, characterized in that at least one catalyst compound of the catalyst is chosen from sodium chloride, sodium iodide, potassium chloride, potassium iodide, calcium chloride, calcium iodide, magnesium chloride, magnesium iodide, ammonium chloride, ammonium iodide, copper chloride, copper iodide, cupric oxide CuO, and titanium oxide TiO₂.
 9. The smoke composition as claimed in claim 3, characterized in that at least one compound of the catalyst is also a compound of the regulating agent.
 10. The smoke composition as claimed in claim 9, characterized in that said “compound at least” of the catalyst and of the regulating agent is chosen from clay, magnesium chloride hexahydrate, phosphates and polyphosphates, that may or may not be hydrated.
 11. The smoke composition as claimed in claim 10, characterized in that the “compound at least” of the catalyst and of the regulating agent is clay, in all its forms, including kaolin.
 12. The smoke composition as claimed in claim 3, characterized in that at least one compound of the aerating agent is also a compound of the regulating agent.
 13. The smoke composition as claimed in claim 12, characterized in that said “compound at least” of the aerating agent and of the regulating agent is chosen from inorganic hydroxides, carbonates and bicarbonates.
 14. The smoke composition as claimed in claim 13, characterized in that said “compound at least” of the aerating agent and of the regulating agent is chosen from magnesium hydroxide, aluminum hydroxide, sodium carbonate, potassium carbonate, calcium carbonate and magnesium carbonate, that may or may not crystallize with water.
 15. The smoke composition as claimed in claim 3, characterized in that the regulating agent also comprises compounds chosen from ammonium carbonates, ammonium bicarbonates and ammonium carbamates, and inorganic salts that crystallize with water molecules, other than magnesium hydroxide, aluminum hydroxide, sodium carbonate, potassium carbonate, calcium carbonate and magnesium carbonate.
 16. The smoke composition as claimed in claim 3, characterized in that the reducing agent comprises at least one organic compound.
 17. The smoke composition as claimed in claim 16, characterized in that said “organic compound at least” is chosen from carbohydrates and derivatives, polyols, organic acids and the salts of said acids, said acids or salts containing at most 9 carbon atoms, and carbon derivatives, such as charcoal, carbon black or graphite.
 18. The smoke composition as claimed in claim 17, characterized in that said “organic compound at least” is starch, sorbitol, glycerol or pentaerythritol.
 19. The smoke composition as claimed in claim 17, characterized in that said “organic compound at least” is chosen from organic hydroxycarboxylic acids and their salts, said acids or salts containing up to 7 carbon atoms.
 20. The smoke composition as claimed in claim 19, characterized in that the reducing agent comprises at least one other organic reducing compound that is chosen from urea, dicyandiamide, melamine and cyanamide, and salts thereof, azodicarbonamide, guanidine and its salts, biguanide and its salts, methylcarbazate and ethylcarbazate, said organic reducing compound being present in a maximum proportion of 12% by weight relative to the weight of the base.
 21. The smoke composition as claimed in claim 1, characterized in that the reducing agent comprises at least one inorganic reducing compound.
 22. The smoke composition as claimed in claim 21, characterized in that the inorganic reducing compound is chosen from sulfur and sulfur oxides, that may or may not be anhydrous.
 23. The smoke composition as claimed in claim 22, characterized in that the inorganic reducing compound is anhydrous or nonanhydrous sodium thiosulfate Na₂S₂O₃.
 24. The smoke composition as claimed in claim 23, characterized in that the sodium thiosulfate is present in a proportion ranging from 1 to 6% by weight relative to the weight of the base.
 25. The smoke composition as claimed in claim 1, characterized in that the oxidizing agent is chosen from nitrates, nitrites, chlorates and perchlorates, iodates and periodates, and peroxides, alone or as a mixture.
 26. The smoke composition as claimed in claim 1, characterized in that the oxidizing agent is present in said base in a proportion ranging from 30 to 70% by weight, and preferably from 40 to 60%.
 27. The smoke composition as claimed in claim 25, characterized in that the oxidizing agent contains ammonium nitrate, present in a proportion ranging from 40 to 60% by weight relative to the weight of the base.
 28. The smoke composition as claimed in claim 25, characterized in that the oxidizing agent comprises from 30 to 70% by weight of said base, preferably 40 to 60%, at least of two different nitrates.
 29. The smoke composition as claimed in claim 28, characterized in that the oxidizing agent comprises from 4 to 16% by weight of said base, of potassium nitrate, sodium nitrate and/or calcium nitrate.
 30. The smoke composition as claimed in claim 28, characterized in that the oxidizing agent also comprises from 1 to 9% by weight of said base, of copper nitrate, aluminum nitrate or magnesium nitrate.
 31. The smoke composition as claimed in claim 25, characterized in that the oxidizing agent comprises at least one peroxide chosen from inorganic peroxyhydrated salts.
 32. The smoke composition as claimed in claim 1, characterized in that said base comprises from 3 to 15% by weight of starch.
 33. The smoke composition as claimed in claim 1, characterized in that it comprises from 6 to 12% by weight of silica.
 34. The smoke composition as claimed in claim 1, characterized in that said base comprises from 2 to 7% by weight of a chlorate or of a perchlorate or of an iodate or of a periodate.
 35. The smoke composition as claimed in claim 1, characterized in that said base comprises from 2 to 7% by weight of a nitrite.
 36. The smoke composition as claimed in claim 1, characterized in that said base comprises from 35 to 45% by weight of ammonium nitrate, from 5 to 12% by weight of sodium nitrate or potassium nitrate, from 6 to 12% by weight of starch, from 4 to 9% by weight of a hydroxycarboxylic acid or of its salt containing at most 6 carbon atoms, from 7 to 10% by weight of silica, and the rest in clay.
 37. The smoke composition as claimed in claim 18, characterized in that said base also comprises one or more halogenated salts, in a proportion ranging from 1 to 7% by weight of the base.
 38. The smoke composition as claimed in claim 1, characterized in that the active ingredient(s) is (are) chosen from bactericidal, fungicidal or insecticidal ingredients.
 39. The smoke composition as claimed in claim 1, characterized in that at least one of the active ingredients is absorbed, in the liquid or pasty state, onto at least one regulating compound. 